/* Relay — single-column product letter */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: #111;
  background: #e8e4dc;
  background-image: repeating-linear-gradient(
    180deg,
    transparent,
    transparent 27px,
    rgba(17, 17, 17, 0.04) 27px,
    rgba(17, 17, 17, 0.04) 28px
  );
}

a {
  color: #111;
}

.u-skip {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: #111;
  color: #fff;
  padding: 0.5rem;
}

.u-skip:focus {
  top: 1rem;
}

.top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.25rem;
  max-width: 640px;
  margin: 0 auto;
  font-size: 14px;
}

.top-logo {
  font-weight: 700;
  letter-spacing: 0.04em;
}

.top-cta {
  text-decoration: none;
  border: 2px solid #111;
  padding: 0.35rem 0.85rem;
  font-weight: 600;
}

.top-cta:hover {
  background: #111;
  color: #f6f4ef;
}

.letter {
  max-width: 640px;
  margin: 0 auto;
  padding: 2.5rem 1.75rem 4rem;
  background: #f6f4ef;
  border: 1px solid #ccc4b8;
  box-shadow: 0 12px 40px rgba(17, 17, 17, 0.08);
}

.serial {
  font-family: ui-monospace, monospace;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #666;
  margin-bottom: 1rem;
}

h1 {
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 1.25rem;
}

.deck {
  font-size: 17px;
  color: #333;
  margin-bottom: 2.5rem;
}

.device {
  margin-bottom: 3rem;
}

.device-screen {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border: 1px solid #111;
  box-shadow: 4px 4px 0 #111;
}

.device figcaption {
  font-size: 12px;
  color: #888;
  margin-top: 0.75rem;
  font-style: italic;
}

.chunk {
  position: relative;
  padding: 2rem 0 2rem 2.5rem;
  border-top: 1px solid #ccc;
}

.chunk::before {
  content: "";
  position: absolute;
  left: 0;
  top: 2rem;
  bottom: 2rem;
  width: 3px;
  background: linear-gradient(180deg, #111 0%, #888 100%);
  opacity: 0.15;
}

.chunk-num {
  position: absolute;
  left: 0;
  top: 2.1rem;
  font-family: ui-monospace, monospace;
  font-size: 11px;
  color: #999;
}

.chunk h2 {
  font-size: 1.125rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.chunk p {
  color: #333;
  margin-bottom: 0.75rem;
}

.spec-list {
  list-style: none;
  font-size: 15px;
  color: #333;
}

.spec-list li {
  padding: 0.35rem 0;
  padding-left: 1rem;
  border-left: 2px solid #111;
  margin-bottom: 0.5rem;
}

.compare {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  margin-top: 0.5rem;
}

.compare th,
.compare td {
  border: 1px solid #bbb;
  padding: 0.5rem 0.65rem;
  text-align: left;
}

.compare thead th {
  background: #eee;
  font-weight: 600;
}

.waitlist {
  display: grid;
  gap: 1rem;
  margin-top: 1rem;
}

.waitlist label {
  display: grid;
  gap: 0.35rem;
  font-size: 13px;
  font-weight: 600;
}

.waitlist input {
  font: inherit;
  padding: 0.55rem 0.65rem;
  border: 1px solid #999;
}

.waitlist button {
  justify-self: start;
  font: inherit;
  font-weight: 600;
  padding: 0.65rem 1.25rem;
  background: #111;
  color: #fff;
  border: none;
  cursor: pointer;
}

.waitlist button:hover {
  background: #333;
}

details {
  border-bottom: 1px solid #ddd;
  padding: 0.75rem 0;
  font-size: 15px;
}

summary {
  font-weight: 600;
  cursor: pointer;
}

details p {
  margin-top: 0.5rem;
  color: #444;
}

.foot {
  max-width: 640px;
  margin: 0 auto;
  padding: 2rem 1.25rem;
  border-top: 1px solid #ccc;
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: #666;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}